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Original post by Evan7788
That's exactly what i did, i reasoned it would take forever to use conjugates...


Im pretty sure both methods would be acceptable.
Original post by Marcus4004
15a 4
15b 7

16a 6
16b 4


I have corrected the exampaper scan at
http://www.thestudentroom.co.uk/showpost.php?p=37685736&postcount=1495

(note UKdragon)
Original post by Evan7788
...

Evan, can you add the usual how hard was this year compared to previous poll?
Original post by Marcus4004
Evan, can you add the usual how hard was this year compared to previous poll?


I think we all know what the answer to that will be.
Original post by tomctutor
I have corrected the exampaper scan at
http://www.thestudentroom.co.uk/showpost.php?p=37685736&postcount=1495

(note UKdragon)


Ok do you want me to include it with the solutions in the same file or as the same post but two different files?

I'm looking at another hour or so perhaps before posting the solutions.
Original post by ukdragon37
Ok do you want me to include it with the solutions in the same file or as the same post but two different files?

I'm looking at another hour or so perhaps before posting the solutions.


Better two different files!
(Sorry thats the best quality I can manage)
Wondered if someone could help me qith question 5, I want to know roughly how many marks I would get.

I made a mistake in finding the direction of QR and got (2,-2,1) instead of (2,-2,-2).

I am sure I done the normal vector then the equation of the plane right as well (ended up with 6x + 6y - 9z = 3), anyone know how many marks I would lose?

Edit: Actually I cant seem to get that equation anymore by working through it now, cant seem to remember what I did write...:frown:
(edited 11 years ago)
Reply 1507
I would but when i go on advanced editing there is no option for it :s.
Reply 1508
Original post by laughylolly
I think we all know what the answer to that will be.


What are you trying to say? :frown:
Reply 1509
For 16b) could you not just do (cos(pi/18)+isin(pi/18)^11 = cos(11pi/18)+isin(11pi/18) and (cos(pi/36)+isin(pi/36)^4 = cos(4pi/36)+isin(4pi/36) then when dividing just subtract

cos(11pi/18 - 2pi/18) + isin(11pi/18 - 2pi/18) = cis(9pi/18) = cos(pi/2)+isin(pi/2)

cos(pi/2) = 0

that for me is easiest and quickest way.
Original post by Evan7788
What are you trying to say? :frown:


Well personally I found 2011 a lot easier. And talking to a bunch of people who have also done the 2011 paper, they found this year a lot harder.

Sorry, that came out a bit wrong didn't it? I meant that we all know what the answer to the poll would be.
(edited 11 years ago)
Original post by pinkpaper94
Wondered if someone could help me qith question 5, I want to know roughly how many marks I would get.

I made a mistake in finding the direction of QR and got (2,-2,1) instead of (2,-2,-2).

I am sure I done the normal vector then the equation of the plane right as well (ended up with 6x + 6y - 9z = 3), anyone know how many marks I would lose?


I don't think you can get marks for consequential errors(except where its a completely separate part of the question where you have to use your answer to a previous part)


So only 1/5 I'm afraid :frown:
Reply 1512
Original post by laughylolly
Well personally I found 2011 a lot easier. And talking to a bunch of people who have also done the 2011 paper, they found this year a lot harder.


Ah i see, although i'd probably say this year was marginally easier.
Original post by Mr Dangermouse
I don't think you can get marks for consequential errors(except where its a completely separate part of the question where you have to use your answer to a previous part)


So only 1/5 I'm afraid :frown:


You must be kidding me :|
Original post by laughylolly
Well personally I found 2011 a lot easier. And talking to a bunch of people who have also done the 2011 paper, they found this year a lot harder.


Everyone says their year is hardest.


Having sat both 2011 and 2012 I can confidently say that 2012 was the easier paper by a fair but.


Apparently the SQA went back and made this year's paper easier after so many teachers complained about the last few questions from last year.
Original post by cr.x
i think it was really different in many ways to the past papers... definitely harder than last year.


Have you seen some of the questions from the last 2 exams?


This year's questions seemed more conventional, bar the lack of a good old differential equation. Even the rate of change question was doable if I had not spit the dummy out.
Original post by why-hello-there
Sorry, I know you're busy. :tongue:

For the last question, everyone is saying to multiply by the complex conjugate (which I tried at first, but got nowhere :tongue:). Eventually, though, I started again and just changed the angles in the numerator to (pi/36) and changed the power to 22-I checked wolfram alpha and it says it's the same thing. I then cancelled out the denominator which left (cos(pi/36)+isin(pi/36))^18
Then, using de moivre's (cos on its own for quickness) cos(18pi/36) =cos pi/2=0?

Would this be alright?


Actually I just looked at the question and read through your solution. It looks completely fine :smile: and rather elegant! I think though I'll do it by a different method (and no, conjugates are not necessary).
Reply 1517
Original post by ukdragon37
Actually I just looked at the question and read through your solution. It looks completely fine :smile: and rather elegant! I think though I'll do it by a different method (and no, conjugates are not necessary).


take it you would be another to use my method?
Original post by PW7
For 16b) could you not just do (cos(pi/18)+isin(pi/18)^11 = cos(11pi/18)+isin(11pi/18) and (cos(pi/36)+isin(pi/36)^4 = cos(4pi/36)+isin(4pi/36) then when dividing just subtract

cos(11pi/18 - 2pi/18) + isin(11pi/18 - 2pi/18) = cis(9pi/18) = cos(pi/2)+isin(pi/2)

cos(pi/2) = 0

that for me is easiest and quickest way.
Original post by ukdragon37
Actually I just looked at the question and read through your solution. It looks completely fine :smile: and rather elegant! I think though I'll do it by a different method (and no, conjugates are not necessary).


Thank you! :smile:
Reply 1519
Original post by Mr Dangermouse
Have you seen some of the questions from the last 2 exams?


This year's questions seemed more conventional, bar the lack of a good old differential equation. Even the rate of change question was doable if I had not spit the dummy out.


I just think like the base question, rate of change, no. 9 matrix question hadn't really come up in previous past papers. Whereas the last 2 exams seemed to follow the usual pattern

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